The flight was supposed at 12:35 a.m. but was delayed for about three hours before it finally took off, sources said.

Authorities were checking surveillance video cameras from the airport to see if any of them show the killer fleeing.

If he’s caught, Mexico will allow his extradition to the US as long as he doesn’t face the death penalty, one source said. New York does not have the death penalty.

The suspect has three previous arrests. In March 2001, he was arrested for stabbing three people in Queens, sources said. That arrest record was sealed for reasons not clear. He was busted twice in 2003 in Nassau County, for assault and criminal contempt.

Cops managed to identify him after a West Village bartender told them he was a regular at the worker’s bar, Bunga’s Den on West 14th Street, and frequented a local tattoo parlor, sources said.

Nicholas Cavello, who owns the 67th Avenue building where the suspect has lived for the past seven years with his brother, said he hadn’t seen Orlando since Saturday. Cavello added that the tenant has been dating a girl from New Jersey.

The explosive developments came as law-enforcement sources said the man he murdered on West 14th Street early Sunday, Michael Jones, 25, may have been the victim of mistaken identity.

The sources said the perp might have thought Jones – a youth coach for the New York Red Bulls — was one of the men who had just broken up a fight between the killer and a female regular in Bunga’s.Den at 137 W. 14th St.

Jones wasn’t at the bar that night, source said.

“The perp is in a bar on 14th Street, he gets into an argument with a female,’’ a source told The Post. “After [the killer]’s arguing with the female, a guy and a couple other males come over, and they intervene. They take the girl away, and they all leave.”

The perp followed the woman and her good Samaritans out, possibly to see the direction they were headed in, sources said. He then went back inside.

“[The perp] continues to drink beer for another half-hour. He then walks out with another woman. As they walk up the block, they pass the victim, who is making a phone call,” the source said.

Jones — a Briton who lived in West Harrison in Westchester and coached Armonk kids — was calling his Mamaroneck girlfriend, Bryeanna Murphy, 23, at the time, sources have said.

The unidentified woman who left the bar at the same time as the killer told cops she continued walking as the madman and Jones exchanged words.

The thug then shoved Jones against a building, pulled a knife and slashed his throat, stomach and head — severing his ear — as the coach fought for his life, video surveillance shows.

The perp “definitely knew what he was doing with the knife. He expertly cut the body, it was not just a random stabbing,’’ one source said.

The woman at the bar told cops she was too drunk to remember many details, and it’s unclear if she actually left the place with the perp or just coincidentally at the same time.

Asked about the scenario of mistaken identity, Police Commissioner Ray Kelly told reporters yesterday, “We’re not ruling that out. It’s still a possibility.”

NYPD detectives were seen at Bunga’s last night talking to workers and inspecting a juke box. It wasn’t clear why. Police already retrieved surveillance video from the bar.

Jones’ father, Perry, said from England that the heartbroken family will fly his body back o their suburban home north of Liverpool for burial.

“We just want to get Michael home as quickly as possible so that we can plan his funeral,’’ Perry Jones told ClickLiverpool.com, a local Web site. “We are just praying that there will not be a long delay in the process of repatriating his body.”

Murphy — who had been with Jones earlier that night — went to church with her parents yesterday to light votive candles for Jones.

The Red Bulls are holding a private memorial service in White Plains this morning for Jones.